From e8ef4ad2a20e1f5e817068bc2101090f49a2124d Mon Sep 17 00:00:00 2001
From: Dhruba Basu <7675102+dhrubabasu@users.noreply.github.com>
Date: Wed, 15 Nov 2023 14:15:17 -0800
Subject: [PATCH] Move `AddUnverifiedTx` logic to `network.IssueTx` (#2310)

---
 vms/platformvm/block/builder/builder.go | 21 +----------------
 vms/platformvm/block/builder/network.go | 30 +++++++++++++++++++++----
 2 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/vms/platformvm/block/builder/builder.go b/vms/platformvm/block/builder/builder.go
index 4d8ad96d132a..63ae6dcb6fea 100644
--- a/vms/platformvm/block/builder/builder.go
+++ b/vms/platformvm/block/builder/builder.go
@@ -102,26 +102,7 @@ func New(
 
 // AddUnverifiedTx verifies a transaction and attempts to add it to the mempool
 func (b *builder) AddUnverifiedTx(tx *txs.Tx) error {
-	txID := tx.ID()
-	if b.Mempool.Has(txID) {
-		// If the transaction is already in the mempool - then it looks the same
-		// as if it was successfully added
-		return nil
-	}
-
-	if err := b.blkManager.VerifyTx(tx); err != nil {
-		b.MarkDropped(txID, err)
-		return err
-	}
-
-	// If we are partially syncing the Primary Network, we should not be
-	// maintaining the transaction mempool locally.
-	if !b.txExecutorBackend.Config.PartialSyncPrimaryNetwork {
-		if err := b.Mempool.Add(tx); err != nil {
-			return err
-		}
-	}
-	return b.GossipTx(context.TODO(), tx)
+	return b.Network.IssueTx(context.TODO(), tx)
 }
 
 // BuildBlock builds a block to be added to consensus.
diff --git a/vms/platformvm/block/builder/network.go b/vms/platformvm/block/builder/network.go
index d263561bfe74..30896e146ff8 100644
--- a/vms/platformvm/block/builder/network.go
+++ b/vms/platformvm/block/builder/network.go
@@ -28,8 +28,11 @@ var _ Network = (*network)(nil)
 type Network interface {
 	common.AppHandler
 
-	// GossipTx gossips the transaction to some of the connected peers
-	GossipTx(ctx context.Context, tx *txs.Tx) error
+	// IssueTx verifies the transaction at the currently preferred state, adds
+	// it to the mempool, and gossips it to the network.
+	//
+	// Invariant: Assumes the context lock is held.
+	IssueTx(ctx context.Context, tx *txs.Tx) error
 }
 
 type network struct {
@@ -121,7 +124,27 @@ func (n *network) AppGossip(_ context.Context, nodeID ids.NodeID, msgBytes []byt
 	return nil
 }
 
-func (n *network) GossipTx(ctx context.Context, tx *txs.Tx) error {
+func (n *network) IssueTx(ctx context.Context, tx *txs.Tx) error {
+	txID := tx.ID()
+	if n.blkBuilder.Mempool.Has(txID) {
+		// If the transaction is already in the mempool - then it looks the same
+		// as if it was successfully added
+		return nil
+	}
+
+	if err := n.blkBuilder.blkManager.VerifyTx(tx); err != nil {
+		n.blkBuilder.Mempool.MarkDropped(txID, err)
+		return err
+	}
+
+	// If we are partially syncing the Primary Network, we should not be
+	// maintaining the transaction mempool locally.
+	if !n.blkBuilder.txExecutorBackend.Config.PartialSyncPrimaryNetwork {
+		if err := n.blkBuilder.Mempool.Add(tx); err != nil {
+			return err
+		}
+	}
+
 	txBytes := tx.Bytes()
 	msg := &message.Tx{
 		Tx: txBytes,
@@ -131,7 +154,6 @@ func (n *network) GossipTx(ctx context.Context, tx *txs.Tx) error {
 		return err
 	}
 
-	txID := tx.ID()
 	n.gossipTx(ctx, txID, msgBytes)
 	return nil
 }